Nagy Péter wrote: Hi,
What you would like to do is IMHO possible in theory, but you have to take into account the capabilities of the math model and the devices you use. If you try to mimic the actual printed piece on your screen (meaning you switch to soft-proof mode in Photoshop) you’re working in the 8-bit realm of the current graphics software and device drivers.
It's worse than that though. AFAIK, Photoshop, ICC and the desktop conspire against using display profiles in Absolute Colorimetric intent, AKA soft proofing side by side mode. 1) As I understand it, Photoshop's proofing mode only uses a pseudo-absolute mode. The print profile is set to Absolute colorimetric while the display profile is left in Relative Colorimetric. So this gives you an impression of the white shift due to the paper color, but adapted to the white point of the display. It isn't actually attempting an absolute colorimetric match. 2) ICC V4 disables display profile Absolute Colorimetric intent by mandating the white point tag be set to D50. So a standard CMM won't render the display output with the absolute intent, ruining any attempt at an absolute colorimetric match. 3) Even ignoring 1) and 2), if your desktop and application have their own GUI elements showing, they will be rendered relative to the native display white point, and so will upset your adaptation state, and make the proofing output appear too yellow. So given all these problems, the only practical approach is to calibrate the display so that it has a white point that matches the paper white. That way a Relative Colorimetric rendering will work for a soft proof side by side comparison. Cheers, Graeme Gill.